Using Inverters for Elevating Machines6-171 I/O Open-phase Protection and Overtorque DetectionTo prevent the machine from falling when the motor is open-phase or a similar situation, enable L8-05 and L8-07 (Input and output open-phase protection selection) and L6-01 to L6-06 (Overtorque detection) (factory set-ting is Disabled).Falling detection or a similar safety measure should also be provided on the machine side. External Baseblock SignalIf the external baseblock command (settings 8 and 9 of H1-01 to H1-06) is input while the motor is running,the motor will immediately coast to a stop. Do not input the external baseblock command while the motor isrunning unless necessary.Make sure that the holding brake operates when using the external base block command for an emergencystop or interlock to start the Inverter.If the external baseblock command is input and immediately reset, the Inverter does not output voltage duringthe value of L2-03 (Min. baseblock time), which factory setting is 0.5 to 2.0 seconds depending on the Invertercapacity. Do not use the external baseblock command in an application where the motor is frequently startedand stopped. Acceleration/Deceleration TimeIf the delay time for the holding brake’s mechanical operation is not taken into consideration and the accelera-tion/deceleration time on the Inverter side is set to a time that is too short, and overcurrent or wear on thebrakes may occur at staring or the load will slip at stopping because the holding brake does not operate ontime. If so, use the dwell function at start described on page 6-174 or the dwell function at stop described onpage 6-175 to tune the timing for the holding brake. Magnetic Contactor on the Inverter’s Output-sideDo not install a magnetic contactor between the Inverter and the motor. If a magnetic contactor must beinstalled because of local electrical codes or regulations or to operate motors with an Inverter, excluding emer-gencies, open or close the magnetic contactor only when the holding brake is fully closed and the Inverter is inbaseblock status with the baseblock signal ON.If the magnetic contactor is opened or closed while the Inverter is controlling the motor or DC injection brak-ing (Zero-speed control), surge voltage or a current from the motor by full-voltage starting may cause anInverter fault.When a magnetic contactor is installed between the Inverter and the motor, set L8-07 (Output open-phase pro-tection selection) to 1 or 2 (Enabled).
